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Full text of "Metallurgy Of Cast Iron"

164                      METALLURGY OF CAST IRON.
of the old set up against its advocates.* Not long ago/as an example, in discussing the merits of working by chemical analysis with an old experienced founder who had never mixed his metals by this method, he expressed the belief that if a cast of nice open-grained pig iron did not give a softer iron than a close-gTained pig mixture it was because of some local condition not being controlled; as, for example, he claimed that the cupola might not have been daubed properly, or the bed not well lighted before the iron was charged, or the charge might not have been placed evenly, or that the stock hung up. Then again, he claimed that it might be due to other conditions, such as are found in bad scrap iron, changeable weather, difference in fuels, fluxes, or variable blast pressures, to cause fast or slow melting, etc. When, as practical foundrymen, we know that such varying conditions may at all times affect mixtures and cause a soft iron to be hard, we are forced to confess that the old-school fellows, may continue their method for years, if they are in any -way prejudiced against the new-school practice, before events may transpire to convince them that by following chemical analysis they will greatly decrease their mishaps, for the simple reason that if an open cast of pig metal does happen to give them a hard iron they have nearly a dozen evils or excuses to which they can charge their poor results.
There are several ways in which self-interest can retard the progress of chemical analysis in founding. As an example we will cite two cases. The first lies in the power of furnacemen knowing the utility of chemical analysis, and lack of that knowledge by the
* For the latest in support of old-school fallacies and retarding the advance of the new, see page 179.n is simply an average of the whole, generally taken from the two ends andith the uncertainty of furnace workings when in urgent need of ten hundred             jon of iron; and Sir........................    2,720     "